Supplemental Inflatable Restraint (SIR)

Code 33:

DERM Circuit Detail:

DESCRIPTION:

At "Turn-on" the DERM monitors the voltage at the 36VLR output (terminal A2) before this output begins to charge. If the diode in the Arming Sensor connected to terminal B (CKT 236) is shorted, "IGNITION 1" voltage will be present at the 36VLR output (terminal A2) as soon as the ignition is turned on. If the DERM detects this Ignition voltage (+/-2 volts) three ignition cycles in a row, History Code 33 will be set.

TEST CONDITION:

Tested once during each ignition cycle at "Turn-on".

FAILURE CONDITIONS:

History Code 33 mill set if the voltage at the 36VLR output of the DERM (terminal A2) is equal to the "IGNITION 1" voltage (+/-2 volts) within the first 500 milliseconds after the ignition is turned on, three ignition cycles in a row.

NOTE: History Code 33 will not set if a history code 51 is set.

CONDITIONS TO CLEAR:

History Code 33 will remain as a History Code until codes are cleared with a scan tool.

ACTION TAKEN:

DERM will not turn on "INFLATABLE RESTRAINT" indicator lamp.

NOTES ON FAULT TREE:

1. Checks if diode on 36VLR circuit in the Dual Sensor is shorted.